#!/bin/bash
#
# filelist - prepare a list of the files in a built system.
# This is for use in comparing two builds, to answer the
# question "can it build itself" ?  Obviously, it can also be
# used to compare two partial builds to see what changed.
#
# Call this script with the path to the root of the system.
# If you are running the new system, the path is probably '/'.
# Alternatively, the system might be mounted at /mnt/lfs, or
# it might have been copied to ~/build1 or wherever.
#
# The output is a single file, filelist-CCYYMMDDhhmm
# e.g. filelist-200510052108
# which contains a list of the files to compare.
# It excludes certain files which are not of interest (/tools,
# /cross-tools, /home) together with any mounted filesystems.
#
# you should run this as a regular user - this will cause files
# in e.g. /root to be ignored.
#
# I like to build a graphical desktop before using a new system
# to see if it can build itself.  Filelist supports this by allowing
# you to list the files at any time.  My normal process is:
#
# 1. Build an LFS system as normal.
# 2. Build some extras before booting (nfs client, ntp, openssh,
#    lynx, dhcp client, etc).
# 3. Boot the new (first) system, set up users, run filelist.
# 4. Build X and whatever else I want to use.
# 5. Build the second system.
# 6. Build the same extras for the second system.
# 7. Boot the second system, to prove it works.
# 8. Reboot to the first system, mount the second system at /mnt/lfs,
#    then run filelist on /mnt/lfs and run the comparison.
# 
# Copyright (C) 2005, 2006 Ken Moffat <ken@linuxfromscratch.org>
#
# All rights reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or (at
# your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
# NON INFRINGEMENT.  See the GNU General Public License for more
# details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#

VERSION="002"

function error() {
	echo "usage:"
	echo "  `basename $0` [--whole-build] path name for output file]"
	echo " e.g. '/' or '/mnt/lfs' or 'build1'"
	echo " use --whole-build to compare files from /tools or /cross-tools"
	echo
	echo "Error: $1"
	exit 1
}


# process the argument, if there is one
# normally, we exclude files in /tools and /cross-tools
EXCLUDE=true

case "$1" in

--whole-build)
	# do NOT exclude cross-tools and tools
	EXCLUDE=
	shift
	;;
--*)
	error "Bad option $1"
	;;

esac


if [ $# -lt 1 ]; then
	error "no argument"
elif [ $1 = "--version" ]; then
	echo "$0 version $VERSION"
	exit
elif [ $# -gt 2 ]; then
	error "more than two arguments"
elif ! [ -d $1 ]; then
	error "not a directory"
fi
if [ $# -eq 2 ]; then
	OUTFILE=$2
	if [ -e $2 ]; then
		echo "output $2 already exists"
		exit
	fi
else
	NOW=`date +%Y%m%d%H%M`
	OUTFILE=~/filelist-${NOW}
fi

if [ "$1" == "/" ]; then
	LOC=$1
else
	# ensure the path or mountpoint ends with a slash
	# because of the seds after the 'find'
	LOC=`echo $1 | sed 's%[^/]$%&/%'`
fi

echo "will create file list in $OUTFILE"
if [ -f $OUTFILE ]; then
	echo "refusing to overwrite $OUTFILE"
	exit 1
fi

# check we can indeed do this
>$OUTFILE
if [ $? -ne 0 ]; then
	echo "error, cannot write to $OUTFILE"
	exit 1
fi

# Explanation of the find command: we exclude any filesystems mounted below
# this path (typically, you are looking at '/' so this excludes /proc /sys
# /dev).  We only care about files, not directories.
# Exclusions - insert whatever we were given at the start of the pathes to
# exclude - this might mean we have '//' in them, but that shouldn't matter.
# /tools* /tools and also e.g. /tools.old if you rename an old version
# /cross-tools* similar, for cross-lfs
# /home/* - in case /home is not a separate filesystem
# /sources/* - where the book thinks you should keep sources
# /tmp/* - we really don't care about any junk left in here
# /misc/* - where I keep buildscripts and stamps
# we then sed it so that / or /mnt/lfs/ or whatever are all converted to '/'.

# At one time, EXCLUDE contained the ! -path strings for cross-tools and tools
# but htat didn't work, so now it is just a marker to control this logic.
if [ -z "$EXCLUDE" ]; then
	find $LOC -xdev -xtype f \
	 ! -path "${LOC}home/*" \
	 ! -path "${LOC}sources/*" ! -path "${LOC}tmp/*" \
	 ! -path "${LOC}misc/*" | sed "s%^${LOC}%/%" | sort >$OUTFILE
else
	find $LOC -xdev -xtype f \
	 ! -path "${LOC}cross-tools*/*" ! -path "${LOC}tools/*" \
	 ! -path "${LOC}home/*" \
	 ! -path "${LOC}sources/*" ! -path "${LOC}tmp/*" \
	 ! -path "${LOC}misc/*" | sed "s%^${LOC}%/%" | sort >$OUTFILE
fi

exit